Flotation apparatus



' Feb. 11, 1930. 7 J. P. RUTH, JR 1,746,682

ELOTATIQN APPARATUS Filed Oct. 8, 1927 a Jwvemfoz Jm k 7 JZuZhJn Patentecl'FebQll;

1 UNITED STATES PATENT: OFFICE- 1 "Jose h entrain, .13., or DENVER, COLORADO- mom-Arron APrARATus Application filed ctober 8,1927. Serial No. 224,876.

. This invention relates to improvements in' machines for recovering mineral values from ore pulp. by the flotation method and has'reference moreiparticularly to an improvement 5 in the construction of the so-called pneumatic type of machine in which the agitation of the pulp is eflected by means of compressed air.

I It is the object of this invention to produce a machine of the type referred to in which the pulp Will be caused to circulate-in closedcurrents, which combine at the center in a single upward current that is mixed with air whereby the sulfide or sulfidized particles My invention, briefly described, consists of I an elongated tank provided withdownwardly and inwardly inclined sides terminating .in

" .ag i'iarrow :flat bottom. Two spaced apart j -L' shaped partitionsextend. the entire'length 5 of the tank a short distance above the bottom,

A row'ofair pipes have their upper ends con- P nected to amanifold or header and pass downwardly between the L-shaped partitions, terf iiminating a'short distance abcve the bottom. Two vertical-walls extend longitudinally of the tank above'.the"pulp level and divide the tank longitudinally into three compartments, perforated plates are connected-to the lower edges of the vertical walls and these-extend downwardlybelow the water level. 1 An ad-' justable deflector is locatedon each side of the "row of pipes and these have their outer surfaces transversely, concave and'upwardly and outwardly inclined so as to deflect the bubbles towards the perforated partitions. When the tank is --filled t'o the proper level the downwardly extending pipes, the air bubbles will mix with the pulp and reduce the specific gravity whereby the pulp will flow upwardly between the partition members and downwardlv alon the inclined sides.

with pulp and air is permitted to flow through all as will be hereinafter more fully ex-v plained.

In order more clearly to-describe the apparatus and its method of operation, reference will now be had to the accompanyingdrawing in which the preferred embodiment thereof has been illustrated and in which:-

Fig. 1 is a longitudinal vertical section taken on line 11, Fig. 2; and

. Fig. 2 is a transverse sectlon taken on line In the drawing I have shown a tank having spaced vertical side members 1, end members 2 and a horizontal bot-tom member 3.

"Inclined sides 4 extend from the inner surfaces of the side members 1 to the bottom member 3 in the manner shown in Fig. 2. This tank is supported on transverse beams 5. ,The upper edges of the vertical sides 1 are provided with removable strips 6, which can be replacedby strips of difierent height, desired. Extending longitudinally along. the outside of the vertical side members are launders 7 which are adapted to receive the "froth that passes over the side strips 6 in the manner illustrated in Fig. 2 and which will hereinafter be more fully described.

Two parallel spaced partition members com.-

rising horizontal planks 8 and downwardly and outwardly inclinedboards or planks 9 extend from one end of the tank to. the other a short distance above the bottom 3 and down below the normal pulp level which-has been indicated by dotted line 10. Vertical side walls 11 extend from one end of the tank to the other and are located parallel to each other and parallel to the side wallsljso as to divide the upper surface of the tank into three compartments which have beenindicated by letters A, B and (1.2 The lower edges of the ver .tical walls 11 are, provided with foraminated plates 12 thatextend down below thenormal pulp level and: terminate a short distance abovet he ,uppefsurface of the planks 8 in the manner shown ,quiteclearly in. Fig. 2. Securedjto the upper edges of walls '11 are transverse bars 13 which serve as supports for a manifold or header'14: that is connected toa source of compresed air supply by means of a nine 15. Extendino downwardly from added one at a time so as to vary the liquid the header 14 are a pluralityof pipes 16 that pass through the space between the partition members and terminate-a short distance above the upper surface of the floor 3. When the air in the manifold 14 is under pressure, air will flow downwardly through the pipe 16 and be liberated near the bottom of the tank. A deflector is employed comprising two wedgeshaped sections 17 and 17 which are identical in shape and size, but which are reversely arranged so as to form a compound deflector of substantially wedge-shape whose apex points downwardly. The inclined sides of this deflector are preferably curved in the manner indicated by numeral 18. Each deflector member is supported by means of two rods 19 which pass upwardly through the transverse bars 13 and have their upper ends provided with screw threads 20 with which the hand wheels 21 cooperate. By rotating the hand wheels, the deflectors may be raised and lowered so as to vary their position with respect to the pulp level 10. The tankis provided at one end with a sluice box 22 through which the pulp is fed into the tank. A baflie 23 is located a short distance inside of the end 2 and serves to direct the pulp downwardly towards the bottom of the tank in the manner quite obvious from the showing in Fig. 1. The other end of the tank is i provided with a discharge spout 24. A bafe 25, which corresponds to the baflie 23 at the other end, extends downwardly to a short distance below the pulp level and is spaced from the discharge end 2, so as to form a passageway through which the pulp travels up- 'wardl on its way to the discharge spout 24. T 1e upper end of discharge wall 2 is provided with a lurality of removable strips 25 which can lie-removed one at a time or level. 1

Let us now assume that the tank is filled with pulp up to the dotted line 10 and that compressed air is supplied through pipes 1 1, 15 and 16. This air will be released near the bottom of the tank andwill form bubbles such as indicated by reference numerals 27 in Fig. 2 and these bubbles will mix with the pulp and reduce its specific gravity, thereby causing it to flow upwardly'between the partition members in the direction indicated by the upwardly and outwardly curved arrows. lVhen these bubbles strike the curved surface 18 of the deflector they will be made to travel outwardly toward the foraminatcd plates 12 and [most of the pulp and air bubbles will pass through the openings in these plates into the; compartments A and C. The froth containing the mineral values will accumulate in the froth compartments A and C and when the froth level has reached a point above the top of the strip 6, the froth will flow into the launders'i in the manner indicated. The sulfide particles and the metallic mineral values direction about .the two parallel partitions so that whatever values fail to become entrained at lirst will have an opportunity to become entrained with the air bubldes on their second or subsequent passages upwardly between the partitions. lulp can be continuously fed into the tank through the sluice 22 and therefore there will be a continuous flow of pulp toward the discharge spout 21. As this pulp moves from the intake toward the discharge end of the tank, it will circulate about the partitions and will therefore have a spiral motion in its passage through the tank. This spiral motion, as above intimated, gives repeated opportunities for the metallic values to become enmeshed in the foam and therefore'theseparation is eXccedinglywell accomplished.

It will be observed from the drawing and from the above description that this flotation apparatus has no rotating parts and that the only movable parts connected therewith are the deflectors 17. and 17. There are, therefore, no bearings to be deleteriously affected by the pulp and there is nothing to wear out.

The deflectors 17 and 17, asabove explained, can be adjusted by means qfjhe hand wheels 21 and it is apparent that when they are located as shown in Fig. 2 with the curved surface 18 almost entirely beneath the pulp 11, the u ward flow of bubbles will be turned outward y so that very little of the air will escape into the compartment B. By moving the deflectors upwardly, it is evident that there will be a greater area between the foraminatcd plates 12 and the deflectors and production of froth and the effectiveness of the apparatus.

I want to call particular attention to the great simplicity of this device and to the fact that by it the pulp is made to travel in a helical path from one end of the tank to the other so as to bring every particle of me tallic value into contact with the air bubbles whereby a Very eliicient operation is obtained. The liberation of the air near the bottom 3 prevents the pulp from settling on the bottom and keeps it always well stirred and agitated.

WVhen the deflectors occupy the position shown inFig. 2, the pulp, together with the air bubbles entrained therewith, will have a passageway of much smaller area to flow .through than when the deflectors are in a more elevated position and therefore the velocityof flo w is greatest ,at this position, wherefore more of the airwill flow into the froth com artment than when thedeflectors are locate higher. If thedeflectors were removed entirely, it is evident. that the greater part of the air would pass upwardly from the air lift intocompartment B and therefore a greater amount of air would be reflector in averticaldirection.

quired to do the same amount of work.

It. will be observed that the air lift compartment, which comprises the space between the partition members as well as that between the vertical'walls 11, has a pulp overflow Whose bottom surface is the top of the planks 8 over which the pulp flows on its way back to the air lift compartment and that this is below the froth overflow. Having described my invention what I claim as new is: e

1. In a pneumatic flotation apparatus, a tank, two parallel spaced partition members extending longitudinally of the tank, said members being spaced from the sides and bottomof the tank and located below the normal liquid level, means for introducing compressed air at spaced intervals along the tank at points adjacent the bottom and directly below and between the spaced partitions,spaced parallel vertical walls extending longitudinally of the tank, the lower edges of said Walls extending a short distance below the normal liquid level and provided with foraminations, an elongatedhorizontal wedge-shaped deflector located between said walls, the point of said deflector extending downwardly and means for adjusting the de- 4. In a flotation apparatus having an elongated tank provided with an upwardly concave bottom surface, means for supplying pulp to one end of said tank, a discharge spout at the other end, a launder" secured to each side of the tank adjacent the top thereof, said launders 'being adapted to catch froth that overflows .the upper edges of the sides, a pair of spaced parallel partition members extending fromone end of the tank to the other, said members being located between the bottom and the normal pulp level, a vertical Wall member located above each partition member, the lower edge of each wall member projecting downwardlyinto the pulp the combination with the above elements of I an elongated deflector located adjacent the pipes between the vertical wall members and means for adjusting the position of the deflector vertically. i

i In testimony whereof I aflix my signature.

JOSEPH P. RUTH, JR.

2. A pneumatic flotation apparatus com prising, in combination, a tankhaving an elongated air lift compartment, an elongated froth compartment on each side of the air lift compartment, means for releasing compressed air near the bottom of the air lift compartment, an elongated deflector located in the air lift-compartment, said deflector having awedgeshaped cross section and arranged with its point projecting downwardly and terminating below the level of the liquid and means for adjusting the deflector vertically. l

3. A pneumatic flotation apparatus comprisinga-tank having an elongated air lift compartment having a froth-compartment along each side, the air lift compartment being separated from the frothing compartments by means of wallswhich are provided with foraminations, means for releasing compressed air near the bottom of the air lift compartment whereby bubbles are formed and means located within the air lift compartment for directing the air bubbles outwardly towards the foraminations and means,

for adjusting the position of the deflectorso as to control the flow of air and pulp through the foraminations', a 

